Exhibit 99.1350CERT

         Certification Pursuant to Section 906 of the Sarbanes Oxley Act

I, Robert C. Doll, Jr., Chief Executive Officer of Merrill Lynch Florida
Municipal Bond Fund of Merrill Lynch Multi-State Municipal Series Trust (the
"Fund"), certify that:

      1.    The N-CSR of the Fund (the "Report") fully complies with the
            requirements of Section 13(a) or 15(d) of the Securities Exchange
            Act of 1934; and

      2.    The information contained in the Report fairly presents, in all
            material respects, the financial condition and results of operations
            of the Fund.

Dated: September 23, 2005


                                       /s/ Robert C. Doll, Jr.
                                       -----------------------
                                       Robert C. Doll, Jr.,
                                       Chief Executive Officer of
                                       Merrill Lynch Florida Municipal Bond Fund
                                       of Merrill Lynch Multi-State Municipal
                                       Series Trust

A signed original of this written statement required by Section 906, or other
document authenticating, acknowledging, or otherwise adopting the signature that
appears in typed form within the electronic version of this written statement
required by Section 906, has been provided to Merrill Lynch Florida Municipal
Bond Fund of Merrill Lynch Multi-State Municipal Series Trust and will be
retained by Merrill Lynch Florida Municipal Bond Fund of Merrill Lynch
Multi-State Municipal Series Trust and furnished to the Securities and Exchange
Commission or its staff upon request.



Exhibit 99.1350CERT

         Certification Pursuant to Section 906 of the Sarbanes Oxley Act

I, Donald C. Burke, Chief Financial Officer of Merrill Lynch Florida Municipal
Bond Fund of Merrill Lynch Multi-State Municipal Series Trust (the "Fund"),
certify that:

      1.    The N-CSR of the Fund (the "Report") fully complies with the
            requirements of Section 13(a) or 15(d) of the Securities Exchange
            Act of 1934; and

      2.    The information contained in the Report fairly presents, in all
            material respects, the financial condition and results of operations
            of the Fund.

Dated: September 23, 2005


                                       /s/ Donald C. Burke
                                       -------------------
                                       Donald C. Burke,
                                       Chief Financial Officer of
                                       Merrill Lynch Florida Municipal Bond Fund
                                       of Merrill Lynch Multi-State Municipal
                                       Series Trust

A signed original of this written statement required by Section 906, or other
document authenticating, acknowledging, or otherwise adopting the signature that
appears in typed form within the electronic version of this written statement
required by Section 906, has been provided to Merrill Lynch Florida Municipal
Bond Fund of Merrill Lynch Multi-State Municipal Series Trust and will be
retained by Merrill Lynch Florida Municipal Bond Fund of Merrill Lynch
Multi-State Municipal Series Trust and furnished to the Securities and Exchange
Commission or its staff upon request.